Information storage medium, and recording/reproducing apparatus and method

ABSTRACT

An information storage medium, and a recording/reproducing apparatus and method, the information storage medium including a plurality of recording layers, each layer including a lead-in area or a lead-out area, a data area, a middle area, and a dedicated area, wherein the data area is flexibly allocated according to data capacity to be recorded in each of the recording layers, the middle area is allocated behind the data area, and the dedicated area is allocated behind the middle area. The dedicated area for a special purpose may selectively be allocated in an outer circumferential area of the information storage medium, i.e., an optical disk including a plurality of recording layers. In particular, optical disks in various formats are provided in which dedicated areas for special purposes can selectively be allocated in outer circumferential areas of the optical disks depending on recording characteristics of the optical disks and the outer circumferential areas.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority of Korean Patent Application No.2004-53784, filed on Jul. 10, 2004 in the Korean Intellectual PropertyOffice, the disclosure of which is incorporated herein in its entiretyby reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

An aspect of the present invention relates to an information storagemedium including a plurality of recording layers, and more particularly,to an information storage medium, i.e., an optical disk, including adedicated area for a predetermined purpose in an outer circumferentialarea thereof, and a recording/reproducing apparatus and method.

2. Description of the Related Art

Optical disks are information storage mediums widely used in opticalpick-up devices, which record/reproduce information in a contactlessmanner. Optical disks are divided into compact disks (CDs) and digitalversatile disks (DVD) according to data recording capacity. Opticaldisks that can be recorded, deleted, and reproduced include 650 MBCD-Rs, CD-rewritables (RWs), 4.7 GB DVD+R/RWs, DVD-random accessmemories (RAMs), and DVD-R/RWs. Optical disks dedicated for datareproduction include 650 MB CDs and 4.7 GB DVD-ROMs. Further,next-generation DVDs having recording capacity of 15 GB or greater areunder development.

FIG. 1A illustrates the structure of a conventional rewritable opticaldisk. FIG. 1B illustrates the structure of a conventional optical diskfor data reproduction. A lead-out area and a lead-in area of therewritable optical disk illustrated in FIG. 1A are almost identical. Thelead-in area of the rewritable optical disk illustrated in FIG. 1Aincludes a control data zone where information regarding the rewritableoptical disk and copy protection is pre-recorded. A rewritable area ofthe lead-in area includes a buffer zone, a reserved zone for future use,an optimum power test zone for optimum power control (OPC), and aninformation zone where information regarding a datarecording/reproducing apparatus or the status of the rewritable opticaldisk is recorded. The optimum power test zone is not required in theoptical disk for data reproduction.

OPC deals with recording user data in the optimum power test zone usingvarious recording powers before the recording and/or reproducingapparatus records the user data on the rewritable optical disk and thendetermining an optimum recording power.

In the conventional rewritable optical disk, the optimum power test zoneof a fixed size is allocated at a fixed location. Thus, it is notpossible to include an additional optimum power test zone or increasethe size of the optimum power test zone. Since recording characteristicsof an optical disk including a plurality of recording layers depend onwhich recording layer data is recorded first, the optimum power testzone for OPC should be placed in consideration of the recordingcharacteristics of the optical disk. In particular, when the optimumpower test zone is allocated in an outer circumferential area of theoptical disk, recording characteristics of the outer circumferentialarea must be considered.

The recording characteristics of the outer circumferential area of theoptical disk including a plurality of recording layers are poorer thanthose of an outer circumferential area of an optical disk having asingle recording layer, which must also be taken into consideration.Similarly, when an area for other purposes is allocated in the outercircumferential area of the optical disk in addition to the optimumpower test zone, the recording characteristics of the outercircumferential area must be considered.

For an optical disk including two recording layers L1 and L2, recordingcharacteristics of the recording layer L2 depend on whether data hasbeen recorded in the recording layer L1 close to a pick-up unit. In thecase of sequential data recording, data is always recorded first in therecording layer L1. When test data is recorded in the optimum power testzone for OPC included in the recording layer L2, a pre-recorded zoneshould be allocated in the recording layer L1 in advance since the testdata must be recorded first in the recording layer L1.

However, the allocation of the pre-recorded zone increases themanufacturing cost of the data recording and/or reproducing apparatus.Hence, whether to allocate the pre-recorded zone and the optimum powertest zone for OPC needs to be selectively determined. In this case, theoptical disk requires an OPC zone at a predetermined location and an OPCzone that can selectively be used by a drive.

In terms of time, to effectively record data in the outercircumferential area of an optical disk having two recording layers L1and L2, the position of a middle area in the optical disk may bedifferent from the same position in an optical disk having a singlerecording layer. In this case, diverse layouts of the optical diskhaving the two recording layers L1 and L2 are required to allocate theoptimum power test zone for OPC in the outer circumferential area.

The same considerations regarding the allocation of the optimum powertest zone must be made when a dedicated area for other purposes isallocated in the outer circumferential area of the optical disk.

SUMMARY OF THE INVENTION

According to an aspect of the present invention, there is provided aninformation storage medium, i.e., an optical disk, including a pluralityof recording layers in which a dedicated area for a predeterminedpurpose can selectively be allocated in an outer circumferential area ofthe information storage medium in consideration of recordingcharacteristics of the information storage medium and the outercircumferential area thereof, and a recording/reproducing apparatus andmethod.

According to an aspect of the present invention, there is provided aninformation storage medium including a plurality of recording layers,each layer including a lead-in area or a lead-out area, a data area, amiddle area, and a dedicated area, wherein the data area is allocatedflexibly according to capacity of data to be recorded in each of therecording layers, the middle area is allocated behind the data area, andthe dedicated area is allocated behind the middle area.

According to another aspect of the present invention, the dedicated areamay be adjacent to the middle area and extend from after the middle areaup to an outer circumference of each of the recording layers.Alternatively, the dedicated area may be adjacent to the middle area andhave a predetermined size.

According to another aspect of the present invention, a start positionand capacity of the dedicated area may be predetermined. The dedicatedarea may be for testing data recording or reproducing conditions.

According to another aspect of the present invention, there is providedan information storage medium including: a first recording layerincluding a first data area flexibly allocated according to capacity ofdata to be recorded on the information storage medium, a first flexiblededicated area part flexibly allocated according to the allocated firstdata area, and a first fixed dedicated area part; and a second recordinglayer including a second data area flexibly allocated according to thecapacity of the data to be recorded on the information storage medium, asecond flexible dedicated area part flexibly allocated according to theallocated second data area, and a second fixed dedicated area part.

According to another aspect of the present invention, the first fixeddedicated area part may include a first dedicated area and the secondfixed dedicated area part includes a second dedicated area, wherein nodata may be recorded in a first corresponding area of the secondrecording layer, which corresponds to the first dedicated area, and in asecond corresponding area of the first recording layer, whichcorresponds to the second dedicated area.

According to another aspect of the present invention, data recordingdirections in the first dedicated area and the second dedicated area mayface each other, and end positions of the first dedicated area and thesecond dedicated area may be flexibly determined.

According to another aspect of the present invention, a first bufferarea may be interposed between the first corresponding area and thefirst dedicated area and a second buffer area may be interposed betweenthe second corresponding area and the second dedicated area inconsideration of an area that cannot be used since the area comes withina radius of a beam extending over the first recording layer when data isrecorded in the second recording layer.

According to another aspect of the present invention, the first fixeddedicated area part may further include a first middle area at apredetermined position in front of the first dedicated area, and thesecond fixed dedicated area part may further include a second middlearea at a predetermined position in front of the second dedicated area.

According to another aspect of the present invention, the second fixeddedicated area part may further include a third dedicated area, and datamay be recorded in a third corresponding area of the first recordinglayer, which corresponds to the third dedicated area, before the thirddedicated area is used. An end position of the third dedicated area maybe flexible or fixed.

According to another aspect of the present invention, the first fixeddedicated area part may further include the first middle area at thepredetermined position in front of the first dedicated area, and thesecond fixed dedicated area part may further include the second middlearea at the predetermined position in front of the second dedicatedarea.

According to another aspect of the present invention, the first flexiblededicated area part may include a third middle area and a fourthdedicated area, and the second flexible dedicated area part may includea fourth middle area and a fifth dedicated area, wherein no data may berecorded in a fourth corresponding area of the second recording layer,which corresponds to the fourth dedicated area, and in a fifthcorresponding area of the first recording layer, which corresponds tothe fifth dedicated area.

According to another aspect of the present invention, data recordingdirections in the fourth dedicated area and the fifth dedicated area mayface each other, and end positions of the fourth dedicated area and thefifth dedicated area may be flexibly determined.

According to another aspect of the present invention, a third bufferarea may be interposed between the fifth corresponding area and thefourth dedicated area and a fourth buffer area may be interposed betweenthe fourth corresponding area and the fifth dedicated area inconsideration of the area that cannot be used since the area comeswithin the radius of the beam extending over the first recording layerwhen data is recorded in the second recording layer.

According to another aspect of the present invention, the secondflexible dedicated area part may further include a sixth dedicated area,and data may be recorded in a sixth corresponding area of the firstrecording layer, which corresponds to the sixth dedicated area, beforethe sixth dedicated area is used. An end position of the sixth dedicatedarea may be flexible or fixed.

According to another aspect of the present invention, no data may berecorded in an area between the first flexible dedicated area part andthe first fixed dedicated area part and an area between the secondflexible dedicated area part and the second fixed dedicated area part.

According to another aspect of the present invention, there is provideda recording/reproducing apparatus including: a writing/reading unitrecording data on an information storage medium or reading the data fromthe information storage medium including a plurality of recordinglayers, each layer including a lead-in area or a lead-out area, a dataarea, a middle area, and a dedicated area; and a control unit flexiblyallocating the data area according to capacity of data to be recorded inthe recording layers, allocating the middle area behind the data area,allocating the dedicated area behind the middle area, and controllingthe writing/reading unit to record the data on the information storagemedium or read the data from the information storage medium.

According to another aspect of the present invention, there is provideda recording/reproducing apparatus including: a writing/reading unitrecording data on an information storage medium including a plurality ofrecording layers or reading the data from the information storagemedium; and a control unit flexibly allocating a first data areaaccording to capacity of data to be recorded on the information storagemedium, a first flexible dedicated area part according to the allocatedfirst data area and a first fixed dedicated area part to a firstrecording layer of the information storage medium, flexibly allocating asecond data area according to the capacity of the data to be recorded onthe information storage medium, a second flexible dedicated area partaccording to the allocated second data area and a second fixed dedicatedarea part to a second recording layer of the information storage medium,and controlling the writing/reading unit to record the data on theinformation storage medium or read the data from the information storagemedium.

According to another aspect of the present invention, there is provideda recording/reproducing method including: flexibly allocating a dataarea according to capacity of data to be recorded in a plurality ofrecording layers, allocating a middle area behind the data area, andallocating a dedicated area behind the middle area to an informationstorage medium including the recording layers, each including a lead-inarea or a lead-out area, the data area, the middle area, and thededicated area and recording the data on the information storage mediumor reading the data from the information storage medium.

According to another aspect of the present invention, there is provideda recording/reproducing method including: flexibly allocating a firstdata area according to capacity of data to be recorded on an informationstorage medium, a first flexible dedicated area part according to theallocated first data area and a first fixed dedicated area part to afirst recording layer of the information storage medium; flexiblyallocating a second data area according to the capacity of the data tobe recorded on the information storage medium, a second flexiblededicated area part according to the allocated second data area and asecond fixed dedicated area part to a second recording layer of theinformation storage medium; and record the data on the informationstorage medium or reading the data from the information storage medium.

Additional aspects and/or advantages of the invention will be set forthin part in the description which follows and, in part, will be obviousfrom the description, or may be learned by practice of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects and advantages of the invention will becomeapparent and more readily appreciated from the following description ofthe embodiments, taken in conjunction with the accompanying drawings ofwhich:

FIG. 1A illustrates the structure of a conventional rewritable opticaldisk;

FIG. 1B illustrates the structure of a conventional optical diskdedicated for data reproduction;

FIGS. 2A and 2B illustrate the structure of optical disks according toan embodiment of the present invention;

FIG. 3 illustrates a case where a beam irradiated to a recording layerL2 passes through a recording layer L1;

FIGS. 4A and 4B illustrate the structure of optical disks according toanother embodiment of the present invention;

FIGS. 5A and 5B illustrate the structure of optical disks according toanother embodiment of the present invention;

FIGS. 6A and 6B illustrate the structure of optical disks according toanother embodiment of the present invention;

FIGS. 7A and 7B illustrate the structure of optical disks according toanother embodiment of the present invention;

FIGS. 8A and 8B illustrate the structure of optical disks according toanother embodiment of the present invention;

FIGS. 9A and 9B illustrate the structure of optical disks according toanother embodiment of the present invention; and

FIG. 10 is a schematic diagram of a recording/reproducing apparatusaccording to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Reference will now be made in detail to the present embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings, wherein like reference numerals refer to the like elementsthroughout. The embodiments are described below in order to explain thepresent invention by referring to the figures.

FIGS. 2A and 2B illustrate the structure of optical disks according toan embodiment of the present invention. The optical disks illustrated inFIGS. 2A and 2B are dual-layer optical disks, each including tworecording layers L1 and L2.

Referring to FIG. 2A, the recording layer L1 includes a first data area1 and a first outer area. The first outer area includes a first middlearea 2, a first unused area 3, a first buffer area 4, a first dedicatedarea 5, a first pre-recorded area 6, and a first unrecorded area 7sequentially disposed from an inner circumference of an outercircumference thereof. The recording layer L2 includes a second dataarea 8 and a second outer area. The second outer area includes a secondmiddle area 9, a second dedicated area 10, a second buffer area 11, asecond unused area 12, a third buffer area 13, a third dedicated area14, and a second unrecorded area 15.

The first data area 1 and the second data area 8 are areas where userdata is recorded. In the first middle area 2 and the second middle area9, a predetermined pattern of data indicating the end of the first andsecond data areas 1 and 8 is recorded. A data recording and/orreproducing apparatus reads and decodes the predetermined pattern ofdata and recognizes that the areas in which the predetermined pattern ofdata is recorded are the first and second middle areas 2 and 9, not thefirst and second data areas 1 and 8. Generally, the predeterminedpattern of data has lead-out properties.

The first through third dedicated areas 5, 10, and 14 are used by thedata recording and/or reproducing apparatus for special purposes. Forexample, the first through third dedicated areas 5, 10, and 14 may beused as test areas for optimum power control (OPC). The first throughthird dedicated area 5, 10, and 14 may be used for other purposes thanas the test areas. For example, information regarding data recordingperformed before a drive records user data may be recorded in the firstthrough third dedicated areas 5, 10, and 14. Also, information regardingwhat is recorded by which data recording and/or reproducing apparatusmay be recorded in the first through third dedicated areas 5, 10, and14.

As their name indicates, the first and second unused areas 3 and 12 areareas that are not used at all. Recording characteristics of opticaldisks including a plurality of rewritable recording layers depend onwhich recording layer data is recorded first. In particular, innercircumferential areas of the optical disks have poorer recordingcharacteristics than outer circumferential areas thereof. Therefore, anarea in the recording layer L2, which corresponds to the first dedicatedarea 5 in the recording layer L1, is designated as the second unusedarea 12 such that no data is recorded in the second unused area 12.Similarly, an area in the recording layer L1, which corresponds to thesecond dedicated area 10, is designated as the first unused area 3 suchthat no data is recorded in the first unused area 3.

If the first and second dedicated areas 5 and 10 are used as test areasand data is to be recorded in the recording layer L2, a laser beampasses through the recording layer L1 and is incident on the recordinglayer L2. The laser beam passes through the first unused area 3 and datais test-recorded in the second dedicated area 10. Then, a recordingcondition for the recording layer L2 is identified in consideration ofattribute parameters of the recording layer L2 in addition to thetest-recording result.

The first, second, and third buffer areas 4, 11, and 13 are formed basedon the eccentricity of the optical disk and a size of an irradiatedbeam. The first, second, and third buffer areas 4, 11, and 13 will nowbe described in more detail with reference to FIG. 3.

FIG. 3 illustrates the recording layer L1 irradiated by a beam 400 andfocusing on the recording layer L2. When the beam 400 is focused on alocation in the recording layer L2 though an object lens 300 of the datarecording and/or reproducing apparatus, an area in the recording layerL1 corresponding to a radius y of the beam 400 is affected by the beam400. The sizes of the first, second, and third buffer areas 4, 11, and13 can be predetermined according to the effects of the beam irradiatedto other recording layers to record data, the size of the beam, and theeccentricity of the optical disk.

The first pre-recorded area 6 is for using the third dedicated area 14.Before the third dedicated area 14 is used, data is pre-recorded in thefirst pre-recorded area 6 in various ways and at various times. Forexample, a pit may be formed in an area designated as a pre-recordedarea before an optical disk is manufactured, and data may be recorded inthe pit. Alternatively, data may be recorded in the first pre-recordedarea 6 in a predetermined way before the data recording and/orreproducing apparatus uses the third dedicated area 14. In the case ofthe third dedicated area 14, since data is test-recorded in a statewhere the recording layer L1 is already recorded, the attributeparameters of the recording layer L2 need not be considered in additionto the test-recording result.

The first and second unrecorded areas 7 and 15 are disposed on theoutermost circumference of the optical disk. No data is recorded in thefirst and second unrecorded areas 7 and 15 due to their poor recordingcharacteristics. The first and second unrecorded areas 7 and 15 may notbe allocated. An unrecorded area may be referred to as an unused areafor users or a blank area.

Referring to FIG. 2A, the first and second middle areas 2 and 9 aredisposed at a predetermined location in the outer circumference of theoptical disk. A flexible capacity is allocated to the first, second andthird dedicated areas 5, 10 and 14, and the first pre-recorded area 6.An outer circumferential boundary between the third dedicated area 14and the first pre-recorded area 6 is determined by the data recordingand/or reproducing apparatus into which the optical disk is loaded.

The structure of the optical disk illustrated in FIG. 2B is identical tothat of the optical disk illustrated in FIG. 2A. However, while theouter circumferential boundary between the third dedicated area 14 andthe first pre-recorded area 6 of the optical disk of FIG. 2A isvariable, the outer circumferential boundary between a third dedicatedarea 14 and a pre-recorded area 6 of the optical disk of FIG. 2B isfixed.

FIGS. 4A through 9B illustrate optical disks including outer areas invarious formats to enhance the usability of the outer areas in recordinglayers when the outer areas increase.

FIGS. 4A and 4B illustrate the structure of the optical disks accordingto another embodiment of the present invention. Each of the opticaldisks is a dual-layer optical disk including two recording layers L1 andL2.

In the present embodiment, when data is to be recorded on the opticaldisk having the two recording layers L1 and L2, if the capacity of userdata to be recorded is smaller than a total recordable capacity of theoptical disk and can be pre-recognized by the data recording and/orreproducing apparatus, the data recording and/or reproducing apparatusdetermines the size of a data area in each of the two recording layersL1 and L2 such that the same amount of user data is recorded in the tworecording layers L1 and L2. Further, different amounts of user data canbe recorded in the two recording layers L1 and L2.

Since a start position of the data area in each of the recording layersL1 and L2 is predetermined, once the size of the data area isdetermined, an end position of the data area can be determined. Thedetermined size of the data area should be smaller than the originalsize of the data area, and, accordingly, the size of an outer area ineach of the layers L1 and L2 should increase.

Referring to FIG. 4A, the recording layer L1 includes a first data area21 and a first outer area. The first outer area includes a third middlearea 22, a third unused area 23, a fourth buffer area 24, a fourthdedicated area 25, a second pre-recorded area 26, and a third unrecordedarea 27, a first middle area 2, a first unused area 3, a first bufferarea 4, a first dedicated area 5, a first pre-recorded area 6, and afirst unrecorded area 7 sequentially disposed from an innercircumference of an outer circumference thereof.

In other words, the structure of the first outer area illustrated inFIG. 2A is repeated in the first outer area of the recording layer L1illustrated in FIG. 4A. However, a start position of the first middlearea 2 is fixed, whereas a start position of the third middle area 22depends on the capacity of the first data area 21.

The recording layer L2 includes a second data area 28 and a second outerarea. The second outer area includes a fourth middle area 29, a fifthdedicated area 30, a fifth buffer area 31, a fourth unused area 32, asixth buffer area 33, a sixth unused area 34, a fourth unrecorded area35, a second middle area 9, a second dedicated area 10, a second bufferarea 11, a second unused area 12, a third buffer area 13, a thirddedicated area 14, and a second unrecorded area 15. In other words, thestructure of the second outer area illustrated in FIG. 2A is repeated inthe second outer area of the recording layer L2 illustrated in FIG. 4A.

In the optical disk illustrated in FIG. 4A, the outer circumferentialboundaries of the second pre-recorded area 26, the sixth dedicated area34, the first pre-recorded area 6, and the third dedicated area 14 arevariable. The outer circumferential boundary is determined by the datarecording and/or reproducing apparatus into which the optical diskaccording to an embodiment of the present invention is loaded.

While the areas on the right side of the second and fourth unrecordedareas 27 and 35 are always allocated, the allocation of the areas on theleft side of the second and fourth unrecorded areas 27 and 35 mayselectively be determined by the data recording and/or reproducingapparatus. In addition, when the areas on the left side of the secondand fourth unrecorded areas 27 and 35 are allocated, the areas allocatedon the right side of the second and fourth unrecorded areas 27 and 35may be or may not be used.

The structure and usage of the optical disk illustrated in FIG. 4B areidentical to those of the optical disk illustrated in FIG. 4A. However,while the outer circumferential boundaries of the second pre-recordedarea 26 and the sixth dedicated area 34 of the optical disk of FIG. 4Bare variable, the outer circumferential boundaries of a firstpre-recorded area 6 and a third dedicated area 14 are fixed.

Based on the structure of the optical disks illustrated in FIGS. 4A and4B according to an embodiment of the present invention, the structureand usage of the optical disks according to other embodiments of thepresent invention will now be described.

FIGS. 5A and 5B illustrate the structure of the optical disks accordingto another embodiment of the present invention. The optical diskillustrated in FIG. 5A does not include the first pre-recorded area 6,the third buffer area 13, and the third dedicated area 14 included inthe optical disk of FIG. 4A. Similarly, the optical disk illustrated inFIG. 5B does not include the first pre-recorded area 6, the third bufferarea 13, and the third dedicated area 14 included in the optical disk ofFIG. 4B.

FIGS. 6A and 6B illustrate the structure of optical disks according toanother embodiment of the present invention. The optical diskillustrated in FIG. 6A does not include the second pre-recorded area 26,the sixth buffer area 33, and the sixth dedicated area 34 included inthe optical disk of FIG. 4A. Similarly, the optical disk illustrated inFIG. 6B does not include the second pre-recorded area 26, the sixthbuffer area 33, and the sixth dedicated area 34 included in the opticaldisk of FIG. 4B.

FIGS. 7A and 7B illustrate the structure of optical disks according toanother embodiment of the present invention. The optical diskillustrated in FIG. 7A does not include the first and second middleareas 2 and 9 included in the optical disk of FIG. 4A. Similarly, theoptical disk illustrated in FIG. 7B does not include the first andsecond areas 2 and 9 included in the optical disk of FIG. 4B.

FIGS. 8A and 8B illustrate the structure of optical disks according toanother embodiment of the present invention. The optical diskillustrated in FIG. 8A does not include first and second middle areas 2and 9 included in the optical disk of FIG. 5A. Similarly, the opticaldisk illustrated in FIG. 8B does not include first and second areas 2and 9 included in the optical disk of FIG. 5B.

FIGS. 9A and 9B illustrate the structure of optical disks according toanother embodiment of the present invention. The optical diskillustrated in FIG. 9A does not include first and second middle areas 2and 9 included in the optical disk of FIG. 6A. Similarly, the opticaldisk illustrated in FIG. 9B does not include first and second areas 2and 9 included in the optical disk of FIG. 6B.

Optical disks having double recording layers have been described above.Optical disks having two or more recording layers may have the samestructure and usage as the optical disks having double recording layers.

In addition, recording data on the optical disks in an opposite trackpass (OTP) direction has been described above, but data may also berecorded in a parallel track pass (PTP) direction.

Further, data may be recorded in a middle area using a pre-recordingmethod or a pre-embossed method. Alternatively, data may be recorded inthe middle area by the recording and/or reproducing apparatus after adata area is used by the data recording and/or reproducing apparatus.

FIG. 10 is a schematic diagram of a recording/reproducing apparatus 100that allocates disk space according to an embodiment of the presentinvention. Referring to FIG. 10, the recording/reproducing apparatus 100includes a writing/reading unit 120 and a control unit 110. Thewriting/reading unit 120 records data in a disk 130, which is aninformation storage medium according to an aspect of the presentinvention, and reads the recorded data to reproduce the data under thecontrol of the control unit 110. The control unit controls thewriting/reading unit 120 to record data in predetermined recording unitsor processes data read by the writing/reading unit 120 to obtaineffective data.

In particular, the control unit 110 may check the capacity of databefore the data is recorded on the disk 130, allocate a data areacorresponding to the capacity of the data to each of a first recordinglayer and a second recording layer, and designate the remaining area asa dedicated area. In this case, a middle area indicating the end of thedata area may be disposed immediately after the data area and thededicated area may be disposed after the middle area. The dedicated areamay be disposed next to the middle area or disposed at a fixed positionregardless of the position of the middle area. Also, the capacity of thededicated area may be flexible or fixed.

If disk space is allocated as illustrated in FIGS. 2A through 9B, thecontrol unit 110 may determine the position and capacity of a bufferarea, a pre-recorded area, or a dedicated area.

As described above, according to another aspect of the presentinvention, a dedicated area for a special purpose may selectively beallocated in an outer circumferential area of an optical disk includinga plurality of recording layers. In particular, according to aspects ofthe present invention, there are provided optical disks in variousformats in which dedicated areas for special purposes can selectively beallocated in outer circumferential areas of the optical disks based onrecording characteristics of the optical disks and the outercircumferential areas.

While the present invention has been particularly shown and describedwith reference to exemplary embodiments thereof, it will be understoodby those of ordinary skill in the art that various changes in form anddetails may be made therein without departing from the spirit and scopeof the present invention as defined by the following claims.

1. An information storage medium comprising a plurality of recordinglayers, each layer comprising a lead-in area and/or a lead-out area, adata area, a middle area, and a dedicated area, wherein the data area isflexibly allocated according to a capacity of data to be recorded ineach of the recording layers, the middle area is allocated behind thedata area, and the dedicated area is allocated behind the middle area.2. The medium of claim 1, wherein the dedicated area is adjacent to themiddle area and extends from after the middle area up to an outercircumference of each of the recording layers.
 3. The medium of claim 1,wherein the dedicated area is adjacent to the middle area and has apredetermined size.
 4. The medium of claim 1, wherein a start positionand a capacity of the dedicated area are predetermined.
 5. The medium ofclaim 1, wherein the dedicated area is for testing data recording and/orreproducing conditions.
 6. An information storage medium comprising: afirst recording layer comprising a first data area flexibly allocatedaccording to a capacity of data to be recorded on the informationstorage medium, a first flexible dedicated area part flexibly allocatedaccording to the allocated first data area, and a first fixed dedicatedarea part; and a second recording layer comprising a second data areaflexibly allocated according to the capacity of the data to be recordedon the information storage medium, a second flexible dedicated area partflexibly allocated according to the allocated second data area, and asecond fixed dedicated area part.
 7. The medium of claim 6, wherein thefirst fixed dedicated area part comprises a first dedicated area and thesecond fixed dedicated area part comprises a second dedicated area,wherein no data is recorded in a first corresponding area of the secondrecording layer, which corresponds to the first dedicated area, and in asecond corresponding area of the first recording layer, whichcorresponds to the second dedicated area.
 8. The medium of claim 7,wherein data recording directions in the first dedicated area and thesecond dedicated area face each other, and end positions of the firstdedicated area and the second dedicated area are flexibly determined. 9.The medium of claim 7, further comprising a first buffer area interposedbetween the second corresponding area and the first dedicated area and asecond buffer area interposed between the first corresponding area andthe second dedicated area, wherein the first and the second buffer areasare based on an area that is not used since the area is within a radiusof a beam extending over the first recording layer when data is recordedin the second recording layer.
 10. The medium of claim 7, wherein thefirst fixed dedicated area part further comprises a first middle arealocated at a predetermined position in front of the first dedicatedarea, and the second fixed dedicated area part further comprises asecond middle area located at a predetermined position in front of thesecond dedicated area.
 11. The medium of claim 7, wherein the secondfixed dedicated area part further comprises a third dedicated area, andthe data is recorded in a third corresponding area of the firstrecording layer, which corresponds to the third dedicated area, beforethe third dedicated area is used.
 12. The medium of claim 11, wherein anend position of the third dedicated area is flexible.
 13. The medium ofclaim 11, wherein the first fixed dedicated area part further comprisesa first middle area located at the predetermined position in front ofthe first dedicated area, and the second fixed dedicated area partfurther comprises a second middle area located at the predeterminedposition in front of the second dedicated area.
 14. The medium of claim13, wherein the first flexible dedicated area part comprises a thirdmiddle area and a fourth dedicated area, and the second flexiblededicated area part comprises a fourth middle area and a fifth dedicatedarea, wherein no data is recorded in a fourth corresponding area of thesecond recording layer, which corresponds to the fourth dedicated area,and in a fifth corresponding area of the first recording layer, whichcorresponds to the fifth dedicated area.
 15. The medium of claim 14,wherein data recording directions in the fourth dedicated area and thefifth dedicated area face each other, and end positions of the fourthdedicated area and the fifth dedicated area are flexibly determined. 16.The medium of claim 15, further comprising a third buffer areainterposed between the fifth corresponding area and the fourth dedicatedarea and a fourth buffer area interposed between the fourthcorresponding area and the fifth dedicated area, wherein the third andthe fourth buffer areas are based on an area that is not used since thearea is within a radius of a beam extending over the first recordinglayer when data is recorded in the second recording layer.
 17. Themedium of claim 14, wherein the second flexible dedicated area partfurther comprises a sixth dedicated area, and the data is recorded in asixth corresponding area of the first recording layer, which correspondsto the sixth dedicated area, before the sixth dedicated area is used.18. The medium of claim 17, wherein an end position of the sixthdedicated area is flexible.
 19. The medium of claim 14, wherein no datais recorded in an area between the first flexible dedicated area partand the first fixed dedicated area part and an area between the secondflexible dedicated area part and the second fixed dedicated area part.20. A recording/reproducing apparatus comprising: a writing/reading unitrecording data on an information storage medium or reading the data fromthe information storage medium comprising a plurality of recordinglayers, each layer comprising a lead-in area and/or a lead-out area, adata area, a middle area, and a dedicated area; and a control unitflexibly allocating the data area according to a capacity of data to berecorded in the recording layers, allocating the middle area behind thedata area, allocating the dedicated area behind the middle area, andcontrolling the writing/reading unit to record the data on theinformation storage medium or read the data from the information storagemedium.
 21. The apparatus of claim 20, wherein the control unit placesthe dedicated area adjacent to the middle area and allocates a fixedsize middle area.
 22. The apparatus of claim 20, wherein the controlunit uses the dedicated area to test data recording or reproducingconditions.
 23. A recording/reproducing apparatus comprising: awriting/reading unit recording data on an information storage mediumcomprising a plurality of recording layers or reading the data from theinformation storage medium; and a control unit flexibly allocating afirst data area according to a capacity of data to be recorded on theinformation storage medium, a first flexible dedicated area partaccording to the allocated first data area and a first fixed dedicatedarea part to a first recording layer of the information storage medium,flexibly allocating a second data area according to the capacity of thedata to be recorded on the information storage medium, a second flexiblededicated area part according to the allocated second data area and asecond fixed dedicated area part to a second recording layer of theinformation storage medium, and controlling the writing/reading unit torecord the data on the information storage medium or read the data fromthe information storage medium.
 24. The apparatus of claim 23, whereinthe first fixed dedicated area part comprises a first dedicated area andthe second fixed dedicated area part comprises a second dedicated area,wherein no data is recorded in a first corresponding area of the secondrecording layer, which corresponds to the first dedicated area, and in asecond corresponding area of the first recording layer, whichcorresponds to the second dedicated area.
 25. The apparatus of claim 24,wherein the control unit controls the writing/reading unit to recorddata in the first dedicated area and the second dedicated area inopposite recording directions and flexibly determines end positions ofthe first dedicated area and the second dedicated area.
 26. Theapparatus of claim 24, wherein a first buffer area is interposed betweenthe first corresponding area and the first dedicated area and a secondbuffer area is interposed between the second corresponding area and thesecond dedicated area based on an area that is not used since the areais within a radius of a beam extending over the first recording layerwhen data is recorded in the second recording layer.
 27. The apparatusof claim 24, wherein the first fixed dedicated area part furthercomprises a first middle area at a predetermined position in front ofthe first dedicated area, and the second fixed dedicated area partfurther comprises a second middle area at a predetermined position infront of the second dedicated area.
 28. The apparatus of claim 24,wherein the second fixed dedicated area part further comprises a thirddedicated area, and data is recorded in a third corresponding area ofthe first recording layer, which corresponds to the third dedicatedarea, before the third dedicated area is used.
 29. The apparatus ofclaim 28, wherein an end position of the third dedicated area isflexible.
 30. The apparatus of claim 28, wherein the first fixeddedicated area part further comprises the first middle area at apredetermined position in front of the first dedicated area, and thesecond fixed dedicated area part further comprises a second middle areaat a predetermined position in front of the second dedicated area. 31.The apparatus of claim 27, wherein the first flexible dedicated areapart comprises a third middle area and a fourth dedicated area, and thesecond flexible dedicated area part comprises a fourth middle area and afifth dedicated area, wherein no data is recorded in a fourthcorresponding area of the second recording layer, which corresponds tothe fourth dedicated area, and in a fifth corresponding area of thefirst recording layer, which corresponds to the fifth dedicated area.32. The apparatus of claim 31, wherein the control unit controls thewriting/reading unit to record data in the fourth dedicated area and thefifth dedicated area in opposite recording directions and flexiblydetermines end positions of the fourth dedicated area and the fifthdedicated area.
 33. The apparatus of claim 32, wherein a third bufferarea is interposed between the fifth corresponding area and the fourthdedicated area and a fourth buffer area is interposed between the fourthcorresponding area and the fifth dedicated area based on an area that isnot used since the area is within a radius of a beam extending over thefirst recording layer when data is recorded in the second recordinglayer.
 34. The apparatus of claim 31, wherein the second flexiblededicated area part further comprises a sixth dedicated area, and datais recorded in a sixth corresponding area of the first recording layer,which corresponds to the sixth dedicated area, before the sixthdedicated area is used.
 35. The apparatus of claim 34, wherein an endposition of the sixth dedicated area is flexible.
 36. The apparatus ofclaim 31, wherein no data is recorded in an area between the firstflexible dedicated area part and the first fixed dedicated area part andan area between the second flexible dedicated area part and the secondfixed dedicated area part.
 37. A recording/reproducing methodcomprising: flexibly allocating a data area according to capacity ofdata to be recorded in a plurality of recording layers, allocating amiddle area behind the data area, and allocating a dedicated area behindthe middle area to an information storage medium comprising therecording layers, each recording layer comprising a lead-in area and/ora lead-out area, the data area, the middle area, and the dedicated area;and recording the data on the information storage medium and/or readingthe data from the information storage medium.
 38. The method of claim37, further comprising placing the dedicated area adjacent to the middlearea and allocating a fixed or flexible size middle area.
 39. The methodof claim 37, further comprising using the dedicated area to test datarecording or reproducing conditions.
 40. A recording/reproducing methodcomprising: flexibly allocating a first data area, according to acapacity of data to be recorded on an information storage medium, afirst flexible dedicated area part, according to the allocated firstdata area and a first fixed dedicated area part, to a first recordinglayer of the information storage medium; flexibly allocating a seconddata area, according to the capacity of the data to be recorded on theinformation storage medium, a second flexible dedicated area part,according to the allocated second data area and a second fixed dedicatedarea part, to a second recording layer of the information storagemedium; and recording the data on the information storage medium and/orreading the data from the information storage medium.
 41. The method ofclaim 40, wherein the first fixed dedicated area part comprises a firstdedicated area and the second fixed dedicated area part comprises asecond dedicated area, wherein no data is recorded in a firstcorresponding area of the second recording layer, which corresponds tothe first dedicated area, and in a second corresponding area of thefirst recording layer, which corresponds to the second dedicated area.42. The method of claim 41, further comprising recording data in thefirst dedicated area and the second dedicated area in opposite recordingdirections and flexibly determining end positions of the first dedicatedarea and the second dedicated area.
 43. The method of claim 42, furthercomprising interposing a first buffer area between the secondcorresponding area and the first dedicated area and a second buffer areabetween the first corresponding area and the second dedicated area basedon an area that is not used since the area is within a radius of a beamextending over the first recording layer when data is recorded in thesecond recording layer.
 44. The method of claim 40, wherein the firstfixed dedicated area part further comprises a first middle area at apredetermined position in front of the first dedicated area, and thesecond fixed dedicated area part further comprises a second middle areaat a predetermined position in front of the second dedicated area. 45.The method of claim 40, wherein the second fixed dedicated area partfurther comprises a third dedicated area, and data is recorded in athird corresponding area of the first recording layer, which correspondsto the third dedicated area, before the third dedicated area is used.46. The method of claim 45, wherein an end position of the thirddedicated area is flexible.
 47. The method of claim 45, wherein thefirst fixed dedicated area part further comprises a first middle area atthe predetermined position in front of the first dedicated area, and asecond fixed dedicated area part further comprises a second middle areaat the predetermined position in front of the second dedicated area. 48.The method of claim 40, wherein the first flexible dedicated area partcomprises a third middle area and a fourth dedicated area, and thesecond flexible dedicated area part comprises a fourth middle area and afifth dedicated area, wherein no data is recorded in a fourthcorresponding area of the second recording layer, which corresponds tothe fourth dedicated area, and in a fifth corresponding area of thefirst recording layer, which corresponds to the fifth dedicated area.49. The method of claim 48, further comprising recording data in thefourth dedicated area and the fifth dedicated area in opposite recordingdirections and flexibly determining end positions of the fourthdedicated area and the fifth dedicated area.
 50. The method of claim 49,further comprising interposing a third buffer area between the fifthcorresponding area and the fourth dedicated area and a fourth bufferarea between the fourth corresponding area and the fifth dedicated area,wherein the third and the fourth buffer areas are based on an area thatis not used since the area is within a radius of a beam extending overthe first recording layer when data is recorded in the second recordinglayer.
 51. The method of claim 48, wherein the second flexible dedicatedarea part further comprises a sixth dedicated area, and data is recordedin a sixth corresponding area of the first recording layer, whichcorresponds to the sixth dedicated area, before the sixth dedicated areais used.
 52. The method of claim 51, wherein an end position of thesixth dedicated area is flexible.
 53. The method of claim 48, wherein nodata is recorded in an area between the first flexible dedicated areapart and the first fixed dedicated area part and an area between thesecond flexible dedicated area part and the second fixed dedicated areapart.
 54. The medium of claim 11, wherein the first through thirddedicated areas are used as test areas for optimum power control. 55.The medium of claim 11, wherein an end position of the third dedicatedarea is fixed.
 56. The medium of claim 13, wherein a start position ofthe first middle area is fixed and a start position of the third middlearea depends on the capacity of the first data area.
 57. The medium ofclaim 19, wherein a right side of the area between the first flexiblededicated area part and the first fixed dedicated area part is allocatedwhile a left side of the area between the first flexible dedicated areapart and the first fixed dedicated area part is selectively determined.58. The medium of claim 19, wherein a right side of the area between thesecond flexible dedicated area part and the second fixed dedicated areapart is allocated while a left side of the area between the secondflexible dedicated area part and the second fixed dedicated area part isselectively determined.
 59. The medium of claim 17, wherein an endposition of the sixth dedicated area is fixed.
 60. An informationstorage medium comprising a plurality of recording layers, each layercomprising a lead-in area and/or a lead-out area, a data area, a middlearea, and a dedicated area, wherein the dedicated area is selectivelyallocated in an outer circumferential area of the information storagemedium.
 61. An information storage medium having dedicated areasselectively allocated in outer circumferential areas based on recordingcharacteristics of the information storage mediums and the outercircumferential areas.